1. Android development basics Introduction,Structure,Development Boncho Valkov.Net Developer

2. Table of Contents 1.About Android and why to use it 2.What knowledge do you need to start  Basics of programming,OOP,Databases 3.What software (IDEs) do you need  Android Studio/Eclipse  Emulator – Genymotion or other 4.Structure of Android app 5.Main components – Intent,Activity,Service,Content Provider,Broadcast Receiver 6.Activities lifecycle 2

3. Table of Contents 7.Debugging and logging 8.Intents, passing data between activities 9.Views. Layout Management 10.Listviews and Adapters 11.Notifications 12.HTTP Networking. AsyncTasks and Callbacks 13.Local Storage – SQLLite and SharedPrefs. Content Provider. 3

4. 4 About Android and why to use it

5. 5  Android is a mobile operating system (OS) based on the Linux kernel and currently developed by Google.  Started back in 2008, today is the most popular mobile OS with 1.5 million daily activations, 1 billion devices in total (as of April 2013). About Android

6. 6 About Android - Architecture

7. 7  The most popular mobile OS  Large community  Extremely well documented APIs  Reuse existing knowledge in  Java development  Uses MVC Why android

8. 8  Basics of programming in some object oriented language like C#, Java or other  OOP principals  Databases – SQL/MYSQL or other  XML What do you have to know to start

9. 9 1.For programming  Android studio – for a couple of months there is official version  Eclipse plus SDK tools 2.Emulator  Genymotion  Integrated emulator in android studio  Test on actual device What software (IDEs) do you need

10. 10  Select API Level  Using Packages like JAVA  Java folder  Res folder  Android Manifest file  Gradle Structure of Android project

11. 11 Main components  Activity  Intent  Service  Content Provider  --------------------  Broadcast Receivers  Fragments  Views

12. 12  Represents a single screen with an user interface plus code that runs behind it  If we have multiple activities – one must be selected as the app’s main activity.  The main activity is similar to the main() function in Java and C# Activity

13. 13  Objects carrying messages from one component to another (within the application or outside it).  Two types of intents: Explicit intents – tell exactly what do you want to start to get some result Implicit intents – tell that you what some result, without specifying how Intent

14. 14  Runs in the background to perform long- running operations.  Doesn’t need to interact with the user. Service

15. 15  Supplies data from one application to others on request.  - Can use different ways to store data (database, files, over a network). Content Providers

16. 16  Respond to broadcast messages from other applications or from the system itself (called events or intents).  Applications can also initiate broadcasts to let other applications know that some data has been downloaded or processed. Broadcast Receivers

17. 17  Kind of sub-activity  Can be placed in an Activity to achieve more modular design.  -You can add or remove fragments in an activity while the activity is running. Fragments

18. 18  Layouts  Widgets  Menu  Drawer  Tabs  Can be created via:  -XML files  Programmatically Views

19. Activity Lifecycle

20. 20  onCreate  onStart  onResume – application is running  onPause  onStop  onDestroy Activity Lifecycle

21. Demo

22. Debugging and logging

23. 23  F8 – step forward  F9 – go next breakpoint  Log.v() -VERBOSE  Log.d() -DEBUG  Log.i() -INFO  Log.w() -WARN  Log.e() -ERROR Debugging and logging

24. Demo

25. Intents, passing data between activities

26. 26 Intents  What is an intent  messages you can pass between your app components  can also send them to components in other apps, and execute a task like playing music, sending email and taking pictures.

27. 27  With an Intent you can  Start activities  Start services  Deliver broadcasts  Pass data Intents

28. 28  Types of intents  Implicit  have not specified a component  they must include enough information for the system to determine which of the available components is best to run for that intent. Intents Intent intent = new Intent (Intent.ACTION_VIEW, Uri.parse("http://www.softuni.bg ")); startActivity(intent);

29. 29 Intents  Implicit

30. 30  Types of intents  Explicit  have specified a component, which provides the exact class to be run  usually is used for starting internal activities Intents Intent intent = new Intent (this,SecondActivity.class); startActivity(intent);

31. 31  Put the data in the intent  Retrieve the data from the intent from the component that has been started, usually in onCreate method  Serializable objects can be passed Passing data between activities Intent intent = getIntent(); String passedData = intent.getExtra(“data”); Intent intent = new Intent (this,SecondActivity.class); intent.putExtra("data","i have been passed"); startActivity(intent);

32. 32  We use the intent filters to deny or allow intents to reach our app’s components.  Restrict access Intent Filters

33. Demo

34. Views. Layout Management

35. 35 Views. Layout Management  Mandatory view props  android:layout_width  android:layout_height  Match parent  Fill parent  Wrap Content

36. 36  Single direction, vertically or horizontally  Specified by the android:orientation attribute  All children are stacked one after another  Can use gravity Linear Layout

37. 37  Displays child views in relative positions  The position of each view can be specified as relative to sibling elements  Can align two elements by right border Relative Layout

38. Demo

39. List Views and Adapters

40. 40  Parts of the ListView:  Rows  Adapter -bridge between a view and the underlying data for that view. Provides access to the data items.  Fast Scrolling  Section Index List Views and Adapters

41. 41 List Views and Adapters  Types of list views and adapters

42. 42 Simple List View <ListView android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/listView" android:layout_alignParentTop="true" android:layout_centerHorizontal="true" />  Create ArrayAdapter  Set Adapter to the listView  Set OnClickListener

43. 43  Most of the time we need something specific  Create custom row  Create Custom Adapter that extents BaseAdapter  Implement required methods Custom List View Adapter convertView = LayoutInflater.from(context).inflate(R.layout.university_row,parent,false);

44. Demo

45. Notifications

46. 46  Three required components  Icon  Content title  Content text  Optional components  Action attached to notification, usually an Activity, it’s done by Pending Intent, by calling set Content Intent Notifications Components

47. 47 Notification sample NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this).setSmallIcon(R.drawable.notification_icon).setContentTitle("My notification").setContentText("Hello World!");  If want to add action to Notification  Create Intent  Create PendingIntent, by PendingIntent.getActivity  Use setContentIntent to attach the pending Intent

48. Demo Along with the live demo

49. HTTP Networking. AsyncTasks and Callbacks

50. 50 Http  Hypertext Transfer Protocol (HTTP)  HTTP is the foundation of data communication for the World Wide Web.  Needs permmitions HttpClient defaultHttpClient = new DefaultHttpClient(new BasicHttpParams()); HttpPost httpPost = new HttpPost(path); HttpResponse response = defaultHttpClient.execute(httpPost);

51. 51  Class that that is being executed on a different thread  Prevent using the Main thread (UI) for time taking operations  Extend class with AsyncTask AsyncTask

52. Demo

53. Local Storage – SQLLite and SharedPrefs. Content Provider.

54. 54  Manage access to a structured set of data  Encapsulate the data, and provide mechanisms for defining data security  The standard interface that connects data in one process with code running in another process. Content Providers

55. 55  Software library that implements a self-contained, zero- configuration, transactional SQL database engine.  The most widely deployed SQL database engine in the world.  Useful tools and queries:  - DB Browser for SQLite  Create, Select, Delete, Update SQLite

56. 56  Shared Preferences Store private primitive data in key-value pairs. Local storage SharedPreferences sp = getSharedPreferences(PREFS, Context.MODE_PRIVATE); Editor editor = sp.edit(); editor.putString("key", "value"); editor.commit(); if (sp.contains(Name)) name.setText(sp.getString(Name, ""));

57. Demo

58. Questions?